scholarly journals Determination of Effective Shear Rate in a Pilot-plant External Loop Airlift Reactor

1998 ◽  
Vol 10 (1) ◽  
pp. 73-84 ◽  
Author(s):  
W.A. Al-Masry ◽  
M. Chetty
Keyword(s):  
Shear Rate ◽  
Pilot Plant ◽  
Airlift Reactor ◽  
External Loop

Determination of Bodenstein number and axial dispersion of a triangular external loop airlift reactor

2021 ◽  
Vol 165 ◽  
pp. 61-68
Author(s):  
Shiva Shadpoor ◽  
Ali Pirouzi ◽  
Hoda Hamze ◽  
Davood Mazaheri
Keyword(s):  
Axial Dispersion ◽  
Airlift Reactor ◽  
External Loop

Computational fluid dynamics of rectangular external loop airlift reactor

2020 ◽  
Vol 18 (5-6) ◽  
Author(s):  
Shivanand M. Teli ◽  
Channamallikarjun S. Mathpati
Keyword(s):  
Large Scale ◽  
Lift Coefficient ◽  
Volume Ratio ◽  
Reynolds Stress Model ◽  
Airlift Reactor ◽  
Experimental Results ◽  
Turbulent Dispersion ◽  
Drag Forces ◽  
External Loop ◽  
Turbulent Models

AbstractThe novel design of a rectangular external loop airlift reactor is at present the most used large-scale reactor for microalgae culture. It has a unique future for a large surface to volume ratio for exposure of light radiation for photosynthesis reaction. The 3D simulations have been performed in rectangular EL-ALR. The Eulerian–Eulerian approach has been used with a dispersed gas phase for different turbulent models. The performance and applicability of different turbulent model’s i.e., K-epsilon standard, K-epsilon realizable, K-omega, and Reynolds stress model are used and compared with experimental results. All drag forces and non-drag forces (turbulent dispersion, virtual mass, and lift coefficient) are included in the model. The experimental values of overall gas hold-up and average liquid circulation velocity have been compared with simulation and literature results. It is seemed to give good agreements. For the different elevations in the downcomer section, liquid axial velocity, turbulent kinetic energy, and turbulent eddy dissipation experimental have been compared with different turbulent models. The K-epsilon Realizable model gives better prediction with experimental results.

scholarly journals Numerical study of the hydrodynamics and mass transfer in the external loop airlift reactor

2021 ◽  
pp. 34-34
Author(s):  
Predrag Kojic ◽  
Jovana Kojic ◽  
Milada Pezo ◽  
Jelena Krulj ◽  
Lato Pezo ◽  
...  
Keyword(s):  
Mass Transfer ◽  
Transfer Coefficient ◽  
Mass Transfer Coefficient ◽  
Airlift Reactor ◽  
Volumetric Mass Transfer Coefficient ◽  
Cfd Model ◽  
Gas Velocity ◽  
Liquid Mass ◽  
External Loop ◽  
Liquid Mass Transfer

The objective of this study was to investigate the hydrodynamics and the gas-liquid mass transfer coefficient of an external-loop airlift reactor (ELAR). The ELAR was operated in three cases: different inlet velocities of fluids, different alcohols solutions (water, 0.5% methanol, 0.5% ethanol, 0.5% propanol and 0.5% butanol) and different concentration of methanol in solutions (0%, 0.5%, 1%, 2% and 5%). The influence of superficial gas velocity and various diluted alcohol solutions on hydrodynamics and gas-liquid mass transfer coefficient of the ELAR was studied. Experimentally, the gas hold-up, liquid velocities and volumetric mass transfer coefficient values in the riser and the downcomer were obtained from the literature source. A computational fluid dynamics (CFD) model was developed, based on two-phase flow, investigating different liquids regarding surface tension, assuming the ideal gas flow, applying the finite volume method and Eulerian-Eulerian model. The volumetric mass transfer coefficient was determined using CFD model, as well as artificial neural network model. The effects of liquid parameters and gas velocity on the characteristics of the gas-liquid mass transfer were simulated. These models were compared with appropriate experimental results. CFD model successfully succeed to simulate the influence of different alcohols regarding the number of C-atoms on hydrodynamics and mass transfer.

Mass transfer in an external-loop airlift reactor: experiments and modeling

1997 ◽  
Vol 52 (21-22) ◽  
pp. 3909-3917 ◽  
Author(s):  
H. Dhaouadi ◽  
S. Poncin ◽  
J.M. Hornut ◽  
G. Wild ◽  
P. Oinas ◽  
...  
Keyword(s):  
Mass Transfer ◽  
Airlift Reactor ◽  
External Loop

DETERMINATION OF URANIUM IN FLOTATION CONCENTRATES AND IN LEACH LIQUORS BY X-RAY FLUORESCENCE

1959 ◽  
Vol 37 (1) ◽  
pp. 20-28 ◽  
Author(s):  
G. L. Smithson ◽  
R. L. Eager ◽  
A. B. VanCleave
Keyword(s):  
Direct Measurement ◽  
Pilot Plant ◽  
Internal Standard ◽  
Liquid Extraction ◽  
X Ray ◽  
Liquid Liquid Extraction ◽  
Northern Saskatchewan ◽  
Plant Operations ◽  
Time Required

X-Ray fluorescence has been applied to the analysis of flotation concentrates obtained from pegmatitic uranium ores occurring in Northern Saskatchewan. Approximate uranium analyses can be obtained by direct measurement on flotation concentrates but more accurate results are obtained by using an internal standard such as strontium or yttrium. The time required for an analysis, as compared to that of conventional chemical or fluorimetric methods, is considerably reduced and flotation pilot plant operations can therefore be more effectively controlled. The method has been extended to include the analysis of sulphate leach liquors obtained from the leaching of pegmatitic ores and their flotation concentrates. Organic phases obtained in liquid – liquid extraction studies can also be rapidly analyzed for uranium by X-ray fluorescence.

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